Fluorescent molecularly imprinted nanoparticles-based paper sensor for rapid detection of Staphylococcus aureus

A fluorescent molecularly imprinted polymer (FMIP)-based paper sensor was constructed for rapid detection of Staphylococcus aureus (S. aureus). The FMIP nanoparticles were prepared by the boronate affinity imprinting strategy based on the interactions between the cell-surface biomolecules and the functional monomer with phenylboronic acid groups. Then, such FMIP nanoparticles were modified with amino groups for subsequent covalently grafting onto the aldehyde-functionalized paper surface, enabling its specific recognition capability to S. aureus. The paper sensor can specifically recognize the target bacteria in 5 min with an imprinting factor as high as 14.0. Such paper sensor can quantitatively detect S. aureus in the range of 10²-10⁶ CFU/mL with a detection limit of 77 CFU/mL, and gave spiked recoveries of 87%-116% in real samples. Combining the operational simplicity with rapid detection, this FMIP-based paper sensor can be coupled with a portable fluorimeter to make a point-of-care device for on-site analysis of S. aureus.